1. Field of the Invention
The present invention relates to an improved roof tile fastening means, and more particularly to a roof tile clip for fastening roofing tile to a roof structure.
2. Description of the Prior Art
Typically, sloping roofs are constructed having a framework of rafters supporting a roof deck (sometimes called a "subroof"), which consists of sheathing and underlayment; the roof deck, in turn, provides a nailing base for the roof surface.
The type of roof deck used depends primarily on the nature of the roof surface material, however, most decks have both sheathing and underlayment. Sheathing is a material that provides the nailing base for the roof surface, and often consists of solid plywood sheathing comprising 4 by 8 foot panels nailed directly to the rafters. The underlayment is sandwiched between the sheathing and the roof surface and usually consists of one or more layers of roofing felt, a thick, fibrous mat that has been saturated and coated with asphalt. Areas subjected to heavy rain or hurricanes, such as the Southeast, often have underlayments consisting of built-up layers of roofing felt and hot-mopped asphalt, to provide an extra measure of waterproofing.
Most sloping roofs are covered with overlapping layers of shingles, and are produced from a variety of materials including, asphalt, wood, or tile. The principle underlying the function of the shingle roof is simple: to shed water that falls on the sloping roof by directing the water over layer upon layer of lapped shingle material until it goes over the side and falls to the ground.
Clay has been a popular choice of tile material in certain regions of the country including the West, the Southwest, and Florida, due to its visual appeal and durability. Furthermore, with the introduction of equally durable concrete tiles, made from a blend of cement, sand, and water, the use of roofing tiles has greatly increased in recent years. Because they are extruded, concrete tiles can be manufactured in a variety of shapes including: flat, ribbed, S-shaped, and even textured to resemble wood. Typically, these tiles measure 12 by 17 inches and are approximately 1/2 inch thick. In addition, the tiles incorporate at least one hole for fastening to the underlying subroof. Typically, the fastening hole is located near the top edge, at the tile "pan", or low point, of an S-shaped tile.
To achieve the desired overlapping configuration, tile is first installed along the roof edge, or eave, then successive layers are installed above, overlapping the previously installed row by approximately 3 inches. This sequence is repeated until the roof is substantially covered, at which point specially formed accessory tiles are installed to cap the remaining ridges.
Typically, roofing tiles are secured to the underlying subroof either by wiring, nailing, or in some instances with screws. While securing roofing tiles in this manner may prove adequate for certain regions of the country, it has been generally considered inadequate for regions subject to high winds accompanied by tornados and hurricanes. For example, when Hurricane Andrew struck South Florida in 1992, thousands of homes were damaged by high winds that stripped roof tops of protective tile covering. As a result, much effort has been directed to strengthening the means by which tile are fastened to the subroof.
One such device that has proven useful in holding down roof tile under high wind loading is commonly called a "hurricane clip". These clips are strap type locking fasteners which are nailed directly to the subroof and clip on to the side edge of each tile thereby providing a second holding point for securing the tile in place. Hurricane clips thus hold the lower tile end, or "nose", thereby preventing the nose from lifting in high winds. While hurricane clips have proven effective in reducing tile loss in high winds, they are often difficult and time consuming to install. In addition, conventional hurricane clips may compromise the water tight integrity of the subroof since the clips must be fastened to the sheathing with nails, thus significantly increasing the number of required subroof penetrations.
An example of such a device is disclosed in U.S. Pat. No. 4,182,090, issued to Aarons, a roof tile fastening clip, having a hook shaped configuration at one end and a nail incorporated at the opposite foot end, for securing tile to a batten. This configuration, however, requires additional fasteners for fixing the clips to the subroof. As a result, additional and undesirable subroof penetrations are required further compromising the watertight integrity of the underlying subroof and increasing installation time.
Similarly, U.S. Pat. No. 4,914,885, issued to Baker et al, discloses an improved roofing tile having an optional cutout provided on an overlying flange thereby permitting an underlying tile to be held with a hurricane clip on the underlying tile flange. The hurricane clip disclosed by Baker, however, also requires subroof penetrations, in addition to those required to fasten the tile, for securing the clip. In addition, Baker teaches the use of specially fabricated roofing tile incorporating a special cutout for accommodating the clip thus limiting its industry acceptance.
U.S. Pat. No. 4,314,433, issued to Hulcombe, which discloses a hurricane clip for use with generally S-shaped tile. Specifically, Hulcombe discloses a method and apparatus for fixing roofing tiles to a roof structure using a roofing tile fixing clip for securing overlapping roofing tiles to the roofing structure. The clip structure, however, is comprised of a generally C-shaped clip having a foot designed to engage a fastener securing a tile, at the roll, to an underlying batten, whereby the clip can then engage an overlapping tile edge. The Hulcombe clip, however, must be fastened to the tile hip thus requiring the use of battens. This arrangement is not suitable, however, for tiles that are configured to be fastened at the tile pan, and that do not require the use of battens.
In addition, a number of other disclosed inventions are directed toward highly specialized fasteners and clips for a variety of surface coverings have also failed to gain widespread industry acceptance. For example, U.S. Pat. No. 5,074,093, issued to Meadows, discloses unique OVERLAPPING ARCHITECTURAL TILES each including a locking ridge for engaging and securing an adjacent panel. U.S. Pat. No. 2,325,124, issued to Gardner, discloses a WEATHER SURFACE COVERING using a special clip to form an arrangement whereby roofing sheets are fastened to sheathing such that no exposed nail holes are present. U.S. Pat. No. 1,775,778, issued to Papalas, discloses a LOCKING STRIP FOR CORRUGATED METAL SHEETS for pressing the edges of the sheet seams together thereby holding said edges against movement. U.S. Pat. No. 1,566,415, issued to Miller, discloses a specialized ROOFING SHINGLE incorporating a retaining device having an extending edge portion for securing an adjacent shingle. All of the aforementioned specialized fastening means are specifically directed toward customized shingles and siding, however, and do not address retaining conventional shingles.
Therefore, there exists a need for a roofing tile hurricane clip for preventing the nose of an overlapping tile from lifting in high winds whereby the clip, and tile upon which said clip is mounted, are secured proximate the upper mounting tile pan edge by a common fastener. It is, therefore, to the effective resolution of the aforementioned problems and shortcomings that the present invention is directed.